Comorbidities and mortality risk among extensive-stage small-cell lung cancer patients in mainland China: impacts of hypertension, type 2 diabetes mellitus, and chronic hepatitis B virus infection.

The present study investigated the impact of major comorbidities, including hypertension, type 2 diabetes mellitus (T2DM), and chronic hepatitis B virus (HBV) infection, on the progression-free survival (PFS) and overall survival (OS) of extensive-stage small-cell lung cancer (ES-SCLC) patients in China. Patients having a pathologic diagnosis of ES-SCLC between 2009 and 2017 were enrolled and grouped according to their specific comorbidities. The PFS and OS for each group were evaluated using the Kaplan-Meier method and Cox proportional hazard models. In total, 632 patients were analyzed. The median PFS (mPFS) of these patients was 9 months [95% confidence interval (CI), 6-12 months]. The mPFS of patients without hypertension or T2DM was 9 months; conversely, it was significantly reduced for patients with hypertension [7 months (P < 0.0001)] or T2DM [5 months (P < 0.0001)]. However, mPFS was not significantly different between patients with and without HBV infection (P = 0.2936). A similar trend was observed for OS as well. Further multivariate analyses showed that the OS of patients with hypertension [hazard ratio (HR), 1.344; 95% CI, 1.073-1.683; P = 0.010] or T2DM (HR, 1.455; 95% CI, 1.134-1.868; P = 0.003) was significantly shorter than that of patients without these comorbidities. Accordingly, mortality risk was the highest in patients with concurrent hypertension and T2DM (HR, 1.665; 95% CI, 1.037-2.672; P = 0.00058). Our study found that hypertension and T2DM may be associated with a worse prognosis in ES-SCLC patients. Considerable attention should be paid to the accompanying anti-comorbidity therapies available for patients with ES-SCLC.